ML060950427
| ML060950427 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 04/20/2006 |
| From: | Thadani M Plant Licensing Branch III-2 |
| To: | Sheppard J South Texas |
| Thadani M | |
| References | |
| TAC MC8622 | |
| Download: ML060950427 (6) | |
Text
April 20, 2006 Mr. James J. Sheppard President and Chief Executive Officer STP Nuclear Operating Company South Texas Project Electric Generating Station P. O. Box 289 Wadsworth, TX 77483
SUBJECT:
SOUTH TEXAS PROJECT, UNIT 1 - RE: EVALUATION OF THE 2005 STEAM GENERATOR TUBE INSPECTIONS (TAC NO. MC8622)
Dear Mr. Sheppard:
By letters dated October 12, 2005, and February 28, 2006, STP Nuclear Operating Company, the licensee for South Texas Project (STP), submitted information summarizing the results of its 2005 steam generator tube inspections at STP Unit 1.
The 2005 tube inspections were performed during refueling outage 12. In addition to these reports, the U.S. Nuclear Regulatory Commission (NRC) staff summarized additional information in a letter dated May 27, 2005. The additional summarized information related to the 2005 steam generator tube inspections of foreign objects found in the steam generators.
The NRC staff has completed its review of these reports and concludes that the licensee provided the information required by its technical specifications and that no additional follow-up is required at this time. The staffs evaluation of the licensees reports is enclosed.
If you have any questions concerning the enclosed NRC staffs evaluation, please contact me at (301) 415-1476.
This completes our effort under TAC No. MC8622.
Sincerely,
/RA/
Mohan C. Thadani, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No.: 50-498
Enclosure:
Summary of Staffs Evaluation cc w/encl: See next page
April 20, 2006 Mr. James J. Sheppard President and Chief Executive Officer STP Nuclear Operating Company South Texas Project Electric Generating Station P. O. Box 289 Wadsworth, TX 77483
SUBJECT:
SOUTH TEXAS PROJECT, UNIT 1 - RE: EVALUATION OF THE 2005 STEAM GENERATOR TUBE INSPECTIONS (TAC NO. MC8622)
Dear Mr. Sheppard:
By letters dated October 12, 2005, and February 28, 2006, STP Nuclear Operating Company, the licensee for South Texas Project (STP), submitted information summarizing the results of its 2005 steam generator tube inspections at STP Unit 1.
The 2005 tube inspections were performed during refueling outage 12. In addition to these reports, the U.S. Nuclear Regulatory Commission (NRC) staff summarized additional information in a letter dated May 27, 2005. The additional summarized information related to the 2005 steam generator tube inspections of foreign objects found in the steam generators.
The NRC staff has completed its review of these reports and concludes that the licensee provided the information required by its technical specifications and that no additional follow-up is required at this time. The staffs evaluation of the licensees reports is enclosed.
If you have any questions concerning the enclosed NRC staffs evaluation, please contact me at (301) 415-1476.
This completes our effort under TAC No. MC8622.
Sincerely,
/RA/
Mohan C. Thadani, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No.: 50-498
Enclosure:
Summary of Staffs Evaluation cc w/encl: See next page DISTRIBUTION PUBLIC RidsNrrDorlLplg KKarwoski LPLIV Reading RidsNrrPMMThadani RidsOgcRp RidsNrrLADJohnson RidsAcrsAcnwMailCenter RidsRgn4MailCenter ACCESSION NO:
- No significant change in the SE input OFFICE NRR/LPL4/PM NRR/LPL4/LA CSGB/BC (A) NRR/LPL4/BC NAME MThadani DJohnson EMurphy* DTerao DATE 4/18/06 4/14/06 03/10/2006 4/20/06 OFFICIAL RECORD COPY
SUMMARY
OF STAFFS EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION 2005 STEAM GENERATOR TUBE INSPECTIONS STP NUCLEAR OPERATING COMPANY SOUTH TEXAS PROJECT, UNIT 1 DOCKET NO. 50-498 By letters dated October 12, 2005 ( Agencywide Documents Access and Management System (ADAMS) Accession No. ML052910372), and February 28, 2006 (ADAMS Accession No. ML060660182), STP Nuclear Operating Company, the licensee for South Texas Project, Unit 1 (STP), submitted information summarizing the results of its 2005 steam generator (SG) tube inspections at STP.
The 2005 tube inspections were performed during refueling outage (RFO) 12. In addition to these reports, the U.S. Nuclear Regulatory Commission (NRC) staff summarized additional information concerning the 2005 SG tube inspections in a letter dated May 27, 2005 (ADAMS Accession No. ML051510378). The additional summarized information related to the 2005 SG tube inspections of foreign objects found in the SGs.
STP has four recirculating SGs designed and fabricated by the Westinghouse Electric Company. The model Delta 94 SGs were put into service in 2000 during RFO 9. Each SG has 7,585 thermally treated Alloy 690 tubes that have an outside diameter of 0.688-inch and a nominal wall thickness of 0.040-inch. The tubes were hydraulically expanded at each end for the full depth of the tubesheet and are supported by a flow distribution baffle, support plates, and anti-vibration bars.
The licensee provided the scope, extent, methods, and results of their SG tube inspections in the documents referenced above. In addition, the licensee described corrective actions (i.e., tube plugging) taken in response to the inspection findings.
As a result of the review of the reports, the NRC staff has the following comments/observations:
No primary or secondary inspections were performed during the last RFO (RFO 11). For the 2005 RFO 12, sludge lancing and post lancing Foreign Object Search and Retrieval (FOSAR) was scheduled for all four SGs. No primary side tube inspections were scheduled for RFO 12.
Several hundred small wire fragments were identified in SG-D. The wire fragments were attributed to a feedwater cable stabilizer that migrated into SG-D during cycle 11 prior to or during the shutdown for RFO 11.
Based on the FOSAR and visual identification of a wear scar, eddy current inspections were performed in SG-D. The bobbin inspections focused on the straight run of the tubes (i.e., up to the top tube support plate) to look for evidence of foreign material and wear from foreign material. Full length tube inspections were only performed on 56 tubes.
The licensee indicated that the eddy current inspection plan was not intended for surveillance credit. Based on the information provided in the submittal, the staff understood this statement to mean that the inspections were not intended to satisfy the periodic requirement to inspect the tubes; however, the results were used to verify the as-found and continued acceptability of the tubes until the next scheduled tube inspections.
Based on the review of the information provided, the staff concludes that the licensee provided the information required by its technical specifications. In addition, the staff concludes that there are no technical issues that warrant follow-up action at this time, since the inspections appear to be consistent with the objective of detecting potential tube degradation, and the inspection results appear to be consistent with industry operating experience at similarly designed and operated units.
Principal Contributor: K. Karwoski Date: April 20, 2006
South Texas Project, Units 1 & 2 cc:
Senior Resident Inspector E. D. Halpin U.S. Nuclear Regulatory Commission Vice President Oversight P. O. Box 910 STP Nuclear Operating Company Bay City, TX 77414 P. O. Box 289 Wadsworth, TX 77483 C. Kirksey/C. M. Canady City of Austin S. M. Head, Manager, Licensing Electric Utility Department STP Nuclear Operating Company 721 Barton Springs Road P. O. Box 289, Mail Code: N5014 Austin, TX 78704 Wadsworth, TX 77483 Mr. J. J. Nesrsta Environmental and Natural Resources Mr. R. K. Temple Policy Director City Public Service Board P. O. Box 12428 P. O. Box 1771 Austin, TX 78711-3189 San Antonio, TX 78296 Jon C. Wood INPO Cox, Smith, & Matthews Records Center 112 East Pecan, Suite 1800 700 Galleria Parkway San Antonio, TX 78205 Atlanta, GA 30339-3064 Director Regional Administrator, Region IV Division of Compliance & Inspection U.S. Nuclear Regulatory Commission Bureau of Radiation Control 611 Ryan Plaza Drive, Suite 400 Texas Department of State Health Services Arlington, TX 76011 1100 West 49th Street Austin, TX 78756 Steve Winn Texas Genco, LP Brian Almon 12301 Kurland Drive Public Utility Commission Houston, TX 77034 William B. Travis Building P. O. Box 13326 Judge, Matagorda County 1701 North Congress Avenue Matagorda County Courthouse Austin, TX 78701-3326 1700 Seventh Street Bay City, TX 77414 Susan M. Jablonski Office of Permitting, Remediation A. H. Gutterman, Esq. and Registration Morgan, Lewis & Bockius Texas Commission on 1111 Pennsylvania Avenue, NW Environmental Quality Washington, DC 20004 MC-122 P.O. Box 13087 Austin, TX 78711-3087 February 2006
South Texas Project, Units 1 & 2 cc:
Mr. Terry Parks, Chief Inspector Texas Department of Licensing and Regulation Boiler Division P. O. Box 12157 Austin, TX 78711 Mr. Ted Enos 4200 South Hulen Suite 630 Ft. Worth, Texas 76109